ANT 201 Quiz 6 Study guide

Emergence of Homo

What was the main characteristic about climate during the Pleistocene (Ice Ages) that was different from what came before?

• Ice ages!
• But icy only in Eurasia
• Characterized by large climatic shifts, and some of the coldest global climates in over 450 million years

Know at least three selective pressures faced by early Homo that came with these changes in climate

• Seasonal environment
• Terrestrial predators
• Heat stress
• Mosaic environments
• Competition with other animals
• Competition among themselves

Know three characteristics of the head of early Homo that are derived (new) from those of Australopithecus

• Rounded cranium 
• Smaller molars and premolars
• Gracile mandible
• Large incisors
• Rounded maxilla (upper jaw)
• Brow ridges
• Cranial capacity > 500cc

In what parts of Africa has early Homo been found?

• East and south africa
• Early homo = Pan African. Not just East/South Africa

Which genera of hominins are found at the same time as early Homo? How is it possible that these closely-related hominins could live in the same places at the same times?

• Homo habilis (early Homo)
• Homo rudolfensis
• Homo naledi ?? 
• Early homo or a late surviving remnant of a population of early homo
• They probably did not compete for the same niche

With which genera were flaked stone tools found? Which one was traditionally considered the toolmaker and why?

• Stone tools found with homo habilis aka "handy man" in Olduvia, Georgia

Emergence of Homo

Know one way the post-cranial (below the neck) skeleton of early Homo is like Australopithecus and one way it is more like later Homo.

• Early homo more like autralopithecus
• Hand bones are more robust
• Much longer arms than legs
• Early homo like later homo
• Foot resembles extant humans suggesting a more striding gait

The earliest specimen of Homo is a jawbone with some teeth in it, and it dates to 2.8 Ma. If it is included in Homo, why could this create a problem with how we define our genus?

• Many things that are placed in "early Homo" are actually more australopith-like.
• Therefore, they should be called Australopithecus Homo, if it is truly a clade, it should only begin with later Homo, which show ALL the derived attributes of Homo

What is the main difference between Homo habilis and Homo rudolfensis? Why does this matter?

• Homo rudolfensis has a larger cranial capacity than homo habilis, face is flatter. This difference indicates who is the ancestor to later homo

Why is the discovery of Homo naledi extremely valuable to paleoanthropologists, but not useful for understanding the origins of Homo?

• Extremely complete skeleton
• At least 12 individuals
• However, too late to be a candidate
• 236-335 thousands years old

Why is a braided stream analogy a better model for human evolution than even a bush analogy might be?

• There are some species that branch off but later converge back together

Earliest Biocultural Record

What is the “First Triumvirate of Paleoanthropology”?

The first triumvirate of paleoanthropology

• Meat eating
• Tool making (stone tools)
• Homo 
• All related and shows in the fossil record 

Know three reasons why knowing the origins of meat-eating is important in human evolution.

•  Meat is a high quality resource (easily converts to energy)
• Fat is even higher quality 
• Essential micronutrients (omega 3 fatty acids and protein) 
• Fueling ability of our brains to get larger 
• Social aspect of meat-eating. Cooperative hunting. Meat eating allowed human ancestors to increase in body size while remaining active and social.
• Meat allowed human ancestors to intensify their use of plant foods which led to the domestication of grains e.g. wheat, rice, maize etc.(Meat reduced the possibility of nutritional deficiency which allowed room for the the exploration of plant-based foods)

How is flaked stone tool use linked to meat-eating in the fossil record? How do both of these things relate to the emergence of Homo? What is the “original paradigm” about this issue? What might be wrong with it?

• The earlier paradigm put the emergence of meat-eating, flaked stone tool manufacture, and Homo at the same time, and related to brain size increase

Over the last six years, the dates for the earliest tool-making, meat-eating and Homo have all changed. How have they changed?

• Earliest tools: 2.6 Ma → 3.3 Ma
• Earliest cut marks: 2.6 Ma → 3.4 Ma
• Earliest Homo: 2.4 ma → 2.8 Ma

What is important about material culture? Know at least three kinds of material culture and when they might be expected to preserve. What do archaeologists study?

• Behavior is expressed materially so we can explore our own past through material culture
• Artifacts (something portable made or modified by humans)
• Stone tools 3.3 Ma
• Ochre (pigments) 280 ka
• Modified bones, teeth, shells, and wood (used as tools or ornaments)
• Bone tools: 1.5 Ma
• Wood tools: 400 ka
• Mobile engravings (stone, bone, antler, clay)
• Features (something created by a human that cannot be moved)
• Stone arrangements
• Hearths or pits
• Post holes
• Structures burials

Earliest Biocultural Record

Why was it not surprising that the earliest stone tools to be found are not Oldowan (Mode 1) after all?

• Because Oldowan tools had to be derived from something. Tool use did not randomly emerge with Homo or even Australopithecus. Other primates had to be using tools as well (e.g. chimp nut-cracking stone)

Know the definitions of: flake, core, Oldowan, Lomekwian, equifinality. Where in Africa have early Oldowan tools been found? How do the Lomekwian and Oldowan differ?

• Flake
• A thin piece of sharp stone that comes off when one stone is hit with another
• Core
• The stone that is hit on
• The flake comes from the core
• Equifinality
•  two different processes with the same result
• Oldowan
• Found in Gona Ethiopia (~2.6 Ma) 
• Lomekwian
• 3.3 million years old (from Kenya)
• Lomekwian is made by smashing one rock down on another resting on the ground. Oldowan is made by holding two stones and cracking them together

Know at least three likely reasons that pre-Oldowan sites were not discovered until recently.

• Researchers not looking in the right places
• Researchers not looking for the right things
• Researchers not having the right mindset. 
• Lack of spatial concentrations of modified stones leading to them being archaeologically invisible

Know two reasons the Dikika cut marks were controversial.

• Controversial because some believed cut marks on fossils were caused by meat-eating and some believed they came from trampling by other animals.
• Early tool use vs no early tool use

Why is the “Human Predatory Pattern” perhaps a more appropriate term than “meat-eating”?

• Eat flesh scraps, brains, and marrow
• Same behavior (percussion) applied to novel material (large ungulate bones)
• Humans scavenged large carcasses at first using percussion and getting those fat packets and fueling brain
• Not ecologically beneficial for humans to go hunting in the trees chasing the animals down bc it's too costly 

How is the “new paradigm” different from the old one?

• New paradigm involves complex tool-making as opposed to regular tool-making, regular HPP as opposed to HPP and the emergence of Later Homo as opposed to the origin of Homo. It occurred 2.6 - 1.6 Ma instead of 3.6 - 2.6 Ma as was previously thought in the original paradigm

How can we know if early Homo were hunters or scavengers? What would be evidence for one or the other?

• Hunting by Homo, followed by carnivore scavenging
• Cut marks under tooth marks
• Animal deaths followed by homo scavenging
• Cut marks only
• Animals killed by carnivores were scavenged by Homo
• Cut marks above tooth marks

Archaic Homo

Be able to name at least three species of Homo that lived in Africa at the same time. Be able to explain, using principles of behavioral ecology, how this is possible.

• Homo ergaster - African
• 1.9 - 1.4 mya
• Homo erectus - Asian
• 1.8 - 1.3 mya
• Homo habilis 
• 2.8 - 1.4 mya
• Homo rudolfensis 
• 2.8 - 1.4 mya
• Behavioral ecology 
• There has to be niche separation in order for primates to co- exist in one habitat 
• Body size, activity pattern, diet, locomotion

How did climate change in Africa about 1.8 Ma? Know three biological adaptations to this change that H. ergaster/erectus had.

• Arid grasslands and rainfall seasonality
• Increased body size
• Reduced arm length
• Narrower pelvis
• Barrel shaped rib cage
• More efficient bipedalism
• Reduce exposure to solar radiation

Know at least three derived and three primitive features of Homoergaster/erectus compared to earlier Homo

Derived:

• -Higher skull
• -Shorter face vertically, less overall prognathism
• -Projecting nose 
• Angular occipital with large torus 
• Football shaped cranium
• Reduced postcanine dentition compared to anterior teeth

Primitive:

• -Brow ridges
• -Receding forehead
• -Flattened skull 
• -Broad flat face
• No chin

Know at least two behavioral things that Homo ergaster/erectus did that were different from earlier Homo

• Enhanced capacity to sweat
• Effected most efficiently by a reduction in body hair
• Body plan and facial structure optimized for heat loss and moisture retention
• Long, narrow body and downward nostrils

Archaic Homo

What is the “obstetric dilemma”? How has it been challenged and what is an alternative?

• Obstetric dilemma: babies had to be born "early", while they could still fit through the gap of the narrower pelvises 
• The metabolic dilemma challenges this by saying that babies are born at a point where their energy demands threaten to outstrip the mother's energy capacity. At that point, human babies' brains still have a lot of growing and developing to do, simply because our adult brains are so large. Because of this we are highly dependent when born.

Know at least three kinds of evidence suggesting that H. erectus may have had life history traits somewhat more like a human than an ape?

• H. erectus had body size dimorphism similar to modern humans (Implies pair bonding)
• Longer-lived individuals in large social units
• Grandmothering hypothesis
• Extremely dependent at birth

What is the Acheulean (Mode 2)? How is it different from Mode 1? What can it tell us about teaching, learning, technical skill, and sociality?

• Acheulean handaxes - more pointy than mode 1. The entire stone is flaked 
• Wide flat base and pointy top
• They are complex to manufacture which means that in order for them to be have replicated, the process had to be taught and socialization had to occur. Possibly the cause of origins of language

Know with what hominin the following first appear: fire, shelter, hafting, engravings, leaving Africa

• Homo erectus